The Audiophile Choice

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I have been using the latest combination of OS X 10.11.6 and iTunes 12.4.2.4 for a day or so now, and have encountered no problems. BitPerfect users ought to be able to apply these two updates with confidence.

I want to tell you a true story, but I’m going to change everything that identifies the actual participants. It’s about two companies who saw each other as their biggest competitors. There was no love lost between them, not to mention countless law suits and counter-suits. These were large and professional public listed companies, one with hundreds and the other with thousands of employees. Professionally managed by people with more PhDs and MBAs than you can shake a stick at. But still …

The global market for ‘Widgets’ is $20-50 Billion dollars per year and growing, and is served by several of the world’s largest international corporations. Widgets are manufactured in colossal volumes on highly automated production lines which run 24/7. The manufacturing process is a multi-stage line, with each stage comprising its own dedicated machine tool. One of these stages is the ‘Widget Tuning’ stage where the performance of each individual ‘Widget’ is precisely ’tuned’ to very tight specifications.

Widget tuning machines are evaluated against three broad parameters – (i) the precision with which they can tune a Widget, (ii) the net throughput with which they can tune Widgets, and (iii) their overall cost of ownership. The preferred technology for Widget tuning was known as OWT (Optical Widget Tuning), and there were two manufacturers which supplied OWT machines to the global Widget industry – Opticorp, and General Optics International (GOI). The total worldwide market for OWT machines varied between $200 and $500 Million annually, and was typically shared 60:40 between Opticorp and GOI, with both vendors generating excellent margins on these product lines.

Widget manufacturers appreciated having two vendors for these expensive manufacturing tools, which sell at up to a million dollars apiece and require comprehensive and reliable support and maintenance. Although the market is quite a large one, it isn’t really large enough to support much more than two vendors considering that the barriers to entry are very substantial. What would happen was, as Opticorp began to stretch their lead in market share, GOI would focus on new technology resulting in improved Widget tuning performance, and would gradually claw back market share. Being the market leader, Opticorp would be more reluctant to risk investing in new technology, but would eventually be obliged to do so to avoid the risk of losing their dominant position. And if neither vendor produced a compellingly differentiated product, the Widget manufacturers would start to pressure them on price.

Overall this ongoing competitive situation was good for the Widget manufacturers. The Widget tuning process was an effective one for them, and they had two highly reliable vendors that they could play off one against the other to keep them both sharp. But Optical Widget Tuning was not their only option. A new technology called Electrical Widget Tuning (EWT) was waiting in the wings. It had the potential to be at least as effective as OWT, but required other changes to be made to the overall design of the Widgets to accommodate it. But so long as OWT remained viable there was no pressing need to abandon it.

So long as OWT remained viable …

Out of the blue, the CEO of GOI made a monumental strategic decision (the specifics of which are not germane to this discussion), and which put GOI deeply into debt. No sooner was this announced than a global financial recession suddenly set in. Within months it became evident that GOI was in desperate financial straits, and talk of possible bankruptcy was in the air. And indeed, the following summer GOI went under. Attempts to sell off their OWT business came to nought as at first they demanded too much for it, and later were forced to lay off so many of the key employees that there was no longer a critical mass that could form a viable acquisition. There was great joy in the corridors of Opticorp as their bitter rival and only OWT competitor bit the dust and left the lucrative OWT market entirely to them.

In the boardrooms of the Widget manufacturers, though, things looked rather different. With Opticorp now their sole supplier, they would have nothing with which to push back against price increases, and there would be limited incentive for Opticorp to invest in advancing their technology rather than pocketing cash. Instead, they decided that they had no choice but to go all out to bring Electronic Widget Tuning to maturity as their preferred Widget tuning technology.

Opticorp insisted that they didn’t see this coming. In internal meetings their product managers gave presentation after presentation showing how OWT met all Widget manufacturing requirements, how EWT would offer no advantage, and how a switch to EWT would be disruptive across the board. In short, gentlemen, EWT was a load of hot air and would never happen. But happen it did, despite Opticorp’s technical analysis being pretty well on the money. What it utterly failed to take into account were the strategic perspectives. Within two years Opticorp’s OWT sales had dropped by 75%, and within another 12 months they had evaporated completely. Shortly thereafter, Opticorp’s CEO was shown the door.

The point of this post is not to show how Opticorp could or should have responded differently. That is actually far from simple, and would form a much more elaborate case study. Instead it is a reflection of how events which would lead to the demise of a highly profitable $250M business within three years were greeted by whoops of celebration, and not a hint of trepidation over how it might end up playing out. And how a proper assessment of the situation failed to be undertaken through hubris and conceit.

As I said, this is a true story, I hope accurately portrayed, and it teaches a valuable business lesson. It really doesn’t matter what size your business is – you need competition, and you have to understand why. Competitors keep you honest. Without competition for your business there is no incentive for you to reduce costs, increase efficiencies, and improve service. There is no incentive for you to invest in making your product better. And ultimately, there is no incentive for your customers to remain interested in it.

For better or for worse, consumers at all levels – whether consumers of shampoo or OWT manufacturing tools – want to have choices. Sometimes it is because people just feel more comfortable when they have choices – but sometimes it is because a well-considered strategy demands alternatives. Where there is no choice there is stagnation, such as is typically the case with things like public transport. Having competition is what keeps any business fresh. Your competitors may want to put you out of business, and you them, but in reality they are your Best Friend. Embrace it!

Let me describe something I was very fortunate to be able to try one time, but which very few of us will get the opportunity to experience. I am talking of entering an anechoic chamber.

An anechoic chamber is a room specially designed for the purpose of conducting carefully calibrated acoustic measurements. In normal rooms, any sound generated anywhere within the room will travel rapidly to all other parts of the room by bouncing off the walls (including the ceilings and floors). Therefore, if we attempt to measure the sound in a room we very quickly find that it is impossible to distinguish between sounds which originate directly from the source and those which have travelled via multiple bounces off the room boundaries. This is important, because these multiple signal paths cause the signal to be reinforced, cancelled out, or anything in between, thereby rendering many forms of measurement entirely useless.

The solution is to create a room in which sound waves, when they hit one of the walls (or floors, or ceilings), is instantly and totally absorbed and none of it is reflected back into the room. Such a room generates no echoes, and is therefore termed ‘anechoic’. These are particularly useful for designing things like microphones and loudspeakers, and enable detailed and accurate measurements to be performed in a way that would be virtually impossible otherwise. You’d think that every loudspeaker manufacturer would have one, but they don’t. They all wish they did, but most of them can’t afford such a preposterously expensive luxury. The best they can hope to do is rent time in somebody else’s (most likely in a university research centre, or some other such institution).

What is particularly instructive is to get somebody to step into an anechoic chamber for the first time, and ask them to sing a song or play an acoustic instrument. You can bet your mortgage that they will stop singing or playing within less than a second. What they hear are sounds so alien to them that they can’t help but stop abruptly. It only works first time, because once you know what is going to happen you aren’t so taken aback.

The sound of a voice or an instrument in an anechoic chamber is so utterly unlike anything you have ever heard before that it just stops you dead in your tracks. Same goes for a loudspeaker playing in an anechoic chamber. It is a totally dry sound, devoid of all character, expression, depth, or life. After stopping abruptly, the second thing you will do is lick your lips, because the sound is so dry, so arid, so utterly parched, that it seems to draw the moisture from every pore in your body. It is a profoundly unnatural environment.And yet, the sound of a voice or an instrument in an anechoic chamber is the most accurate representation of that sound. That is precisely what that voice or instrument actually sounds like. Only the sounds travelling directly from the source to the listener will reach the listener. All other sounds will be totally absorbed as soon as they hit any of the walls. This is as accurate as it gets.Outside of the anechoic chamber, the sound you hear is the sound of that instrument playing in a given room. The difference between what you heard inside the chamber and outside is the contribution of the room to the sound. That contribution is colossal. Indeed it is fundamental to how we perceive the sound. The magnitude of the difference serves to ram home the point that everything we hear every day is the product of the various sound sources modified by the environments in which we both exist. The same orchestra, for example, playing in two different concert halls often sounds like two different orchestras.

This is important to grasp, because it serves to illustrate the futility of one of the holy grails of the audio industry – or more precisely of many of the critics who presume to influence the industry as to what it should be doing. This particular sacrament requires that the goal of a high-end audio system is to recreate the sound of the original instrument. But the sound of the original instrument is the desiccated sound from the anechoic chamber, and that is not what people want to hear. What they want to hear is the sound of the original instrument played in the original location, but they want to replay it in a different location.That presents us with two separate philosophical problems. First, how are we to know what the original performance actually did sound like in the original location? Unless we were there at the time, we can’t. Second, our loudspeakers are located in their own separate and different acoustic environment. If ‘simply’ reproducing the musical instruments themselves in our own listening environment is challenging enough, it is a different challenge entirely to reproduce the audio environment of one room inside an entirely different room. Just consider recording a violin in an anechoic chamber, and then trying to reproduce the sound of that anechoic chamber in your own listening room. Take it from me, it is not possible to come even close.So what is it we actually want from our systems? I believe we just want to be convinced. We listen to something and ask ourselves how convinced we are by the illusion that our system has created. The best sound systems do recreate a good illusion of a complete acoustic space. However, for most – if not all – of our recordings, we have no idea whether that space is the same as the one in which the recording was made. But if we can be convinced by what we hear – transported into a listening experience – surely that is all we can realistically ask. I have long ago stopped asking myself if the sound I was getting was ‘correct’. There is no ‘correct’. Nowadays I ask only whether – and to what degree – I am convinced.

I think this goes some way to explaining the pangs that most of us face as we periodically upgrade our sound systems. Critics charge that we are never satisfied, so why bother in the first place. And there is a lot of truth to that. We buy a system, express our happiness with it, listen to it for a few years, and then upgrade it. Rinse and repeat. With each new system, not only are we satisfied that it is better than the old system, but suddenly the old system – to which we were formerly devoted – is now somehow inadequate and no longer lovable (other than through the distorted lens of nostalgia). We cannot go backwards down the audio path and still retain the same sense of joy that powered us on the way up. All this, of course, assumes that the upgrade path was always followed wisely and judiciously.

What is happening, I suggest, is that on each path up the upgrade chain we are re-setting the bar against which our system’s ability to ‘convince’ us is measured. The whole point of a significant upgrade is to significantly enhance your system’s ability to convince you that it is better recreating the original soundscape. If it can pull that off, it will permanently re-set your bar. It now takes an even greater level of fidelity to improve upon the trick of convincing us. Once you’ve heard something, you can’t ‘unhear’ it.

When I was a young man just setting out with this hobby, most critical evaluation of audio systems – particularly loudspeakers – was focussed on the degree to which the sound took on identifiable tonal colourations. And indeed, back in those days colourations were indeed a dominant factor. One product which I recall having a particular impact in the marketplace was the Kef R104aB loudspeaker, which was noted for having particularly low levels of colouration. I used a pair once for a few weeks and confirmed that yes, indeed, they did have a particularly uncoloured sound. But at the end of my time with them I realized that while they were undeniably uncoloured, they didn’t seem to float my boat any more as a consequence.

I wasn’t smart enough yet for the penny to drop, but yes, shortly thereafter it did so. I have long since realized that for my own particular musical enjoyment, tonal colourations are not a major limiting factor. I am more than willing to put up with them if they are the price I have to pay to realize the type of performance which does float my boat, which are imaging stability and soundstaging, dynamic range (both micro and macro), and what is dismissively called PRAT (Pace, Rhythm And Timing). With all those requirements satisfied, I am willing to put up with tonal colourations that other people might find to be cause for criticism. Having said that, though, major advances have been made in the elimination of tonal colourations since the good old ’70’s.So that’s where I put my stick in the ground. As far as tonality is concerned there are no absolutes. Tonal colour is only partially provided by the instrument itself, and is dominated by the acoustics of the room. So when it comes to judging sound reproduction there can be such thing as Harry Pearson’s much vaunted “Absolute Sound”. There are no absolute points of reference other than an anechoic chamber, and nobody would want to listen to anything that sounded like that. The most important milestone of any audiophile journey is when you finally understand what it is that YOU want out of your system – whatever that is – and achieve comfort in the knowledge that that is way more important than what some other audiophile wants out of his.BTW, have any of you figured out the reference in this post’s title? 🙂

When I took delivery of my new PS Audio BHK300 Signature mono block amplifiers, together with a PS Audio P10 Power Regenerator, it presented me with an immediate practical problem. Those three units replaced the single unit of my Classé CA-2300 power amplifier which was installed in the bottom shelf of my “SolidSteel” equipment rack. All three PS Audio units share the same chassis, one which makes them comparable in size (and weight) to the Classé unit. So there was room for only one of the new trio in the SolidSteel rack. It was determined that the P10 would go in the rack, while the BHK300s – which could maybe profit from being located nearer the loudspeakers – would have to find a place to sit on the floor.

This new aesthetic immediately raised a question in my mind. While the SolidSteel rack attempted to provide a solid mechanical ground for the P10 via its three spiked feet sitting in conical cups, sitting the BHK300s directly on the suspended wooden floor did not seem so smart. Nonetheless that would have to suffice, while I thought about how I could provide a better solution.

Forced to consider the situation from theoretical as well as practical considerations, I immediately wondered about the relative benefits of a mechanical ground vs an isolation platform. The idea of a solid mechanical ground is that any vibrations in the product will be efficiently coupled out – just like any residual electrical signals in the equipment chassis will be efficiently coupled out to electrical ground via the ground wire in its power cord. Such an approach – whether electrical or mechanical – requires that the ‘ground’ we are coupling to be a true ground. Now, if my house were built directly on granite bedrock, which I exposed to form the floor of my listening room, a mechanical grounding approach could be ideal. But my house isn’t like that. I have a suspended wooden floor to which my speakers are coupled via their own ‘mechanical ground’ connection. The speakers are therefore in all likelihood transmitting a substantial proportion of any mechanical energy generated within their cabinets into the wooden floor and energizing it. The sound waves propagating back and forth around the room also energize the suspended floor, as do people walking about in the house.

Therefore, if I sit my amplifiers on a support table design which provides a solid ‘mechanical ground’ coupling to the floor, it seems that all this will do is potentially couple vibration from the floor up into the chassis of the amplifier just as efficiently as it would in the other direction. If there were more vibrations in the amplifier than in the floor, then it might be ideal. But I don’t think that is likely to be the case here. So a ‘mechanical ground’ approach might actually cause more problems than it would solve.

The alternative, if the thinking is that the floor represents a source of vibrations from which the chassis of the BHK300s are to be protected, is an isolation system. This is simply a mechanical system between the BHK300s and the floor which absorbs any incoming vibrations. Those of you who still own a turntable will know exactly what I’m talking about. Any turntable worth its salt will contain its own built-in isolation system, although all but the most extreme designs will still benefit from sitting on some sort of external isolation table.

The core of an isolation system is a damped spring. If you sit something heavy on a theoretically perfect spring, and tap down on it to provoke a bounce, then it will continue to bounce away forever, at a frequency determined by the stiffness of the spring and the weight of the object. If you introduce any damping into the system this will cause the bouncing to die down. The greater the amount of damping the more rapidly it will die down.

Consider a car driving along a rutted road. The car is a heavy object sitting on a damped spring (i.e. its suspension). A car driving along a rutted road is very similar to the same car standing still on a vibrating road. The purpose of the car’s suspension can be thought of as trying to isolate the occupants of the vehicle from the vibrations of the road. In truth a car’s suspension designer has a lot more on his mind than your comfort, but lets ignore that (although if you imagine a 1970’s Cadillac you might not be too far off the mark). The mass-on-a-spring will typically have a resonant frequency. If you push down on the fender of your car and suddenly release it, that is the frequency at which it will bounce up and down. The suspension’s damping determines how quickly the bouncing dies out. A modern car is typically very well damped – your 1970’s Caddy less so.

An isolation system designed this way tends to pass frequencies lower than the resonance (natural bouncing) frequency, and absorb the higher frequencies. That way, your old Caddy can drive comfortably along even a Montreal highway, smoothing over all but the biggest bumps, which are transmitted into the cabin. Damping is necessary for two reasons. First, because damping is what actually absorbs the vibrations fed into the system, turning them into heat which is conducted away. Second, because the amount of damping determines how well the isolator attenuates the frequencies it is designed not to pass.

Leaving the old Caddy to one side, for my audio application I want to make sure that my BHK300s are isolated from all frequencies at 20Hz and above. In fact, the lower the better. In my mind, my ideal would be something like a 1Hz resonance, with a small amount of damping that would allow the 1Hz bounce to die out over something like 4-5 seconds. Armed with these design objectives I can sharpen my pencil, sit down, and work out spring rates, damping factors, masses and so forth. And if I was designing something in a professional context that’s how I would approach it. But that’s not what’s happening here.

All I wanted was a simple test bed to see whether any of this stuff actually had any audible effect in my system. What I came up with was a Typhoon 17” x 13” Butcher Block which would form the base of my isolation table, and happened to be the exact same dimensions as the BHK300 chassis. Plus it looks good, and has the practical convenience of four sturdy, built-in legs. As a platform, Butcher Block is a mechanically well-damped material, which is a plus. For my damped springs I decided to use a high-technology pneumatic approach. I bought a set of 12.5” inner tubes for Stroller/Pushchair wheels. The idea was to inflate the inner tube, lie it on its side on the Butcher Block, and sit the BHK300 directly on top of it.

My calculations suggested that those inner tubes could support the weight of the BHK300 without my needing to inflate them to anywhere near their maximum rated air pressure, so I felt confident that the weight of the monoblocks wouldn’t just burst them. As it happens, without the tyre to constrain their expansion, you cannot pump these things up anywhere near their rated pressure! All I could do was pump them up as much as I felt they would safely sustain, and see how I got on. The pressure was too low to register on my automobile tire pressure gauge, so I can’t tell you what the actual pressure was. But that’s fine, because my target pressure was also too low to register!

Since the weight in the BHK300s is not conveniently centred, you have to position the inner tubes slightly to the right of centre on the Butcher Block. To my surprise it proved easy to get it lined up so that the monoblocks sit nice and level. See the photograph. Also to my surprise – and great pleasure – this arrangement proved to have a resonant frequency of ~1Hz and a natural resonance which damps out in 4-5 seconds. This is exactly what I thought in advance might be my ideal setup. This is great news, because manhandling those 83lb monoliths every time you want to make a change is not my idea of fun.

Of course if the isolation method is right, the mechanical grounding method must be wrong, no? I had one unused inner tube, so I pumped it up and put it under the P10 on the bottom shelf of the SolidSteel rack. This inner tube turned out be a bit narrower than the other two, and provides the P10 (a mere 73lb lightweight) with a resonance frequency more like ~5Hz, and is slightly more damped than the monoblocks. If I decide that makes a difference I can always shell out another $10 for one of the wider tubes.

So, how does it all sound? Let’s have a listen.

At this point I am somewhat concerned at the possibility of losing credibility. The changes I am hearing are not subtle. No, not subtle at all. Have you ever changed a pair of interconnects or speaker cables? How about a USB cable or a power cord? There is no doubt in my mind that those components can make a real and valuable contribution to the performance of a high-end audio system, particularly in the area where I operate, where vastly diminishing returns are the order of the day. But for sure the changes engendered by such tweaks are definitively subtle. I’m sure many people might listen along as I audition a pair of interconnects and shrug their shoulders, whereas I might conclude that one of the sets is worth an investment of a thousand dollars. Still others, not content with merely shrugging their shoulders, will fire off a spate of spiteful invectives on every audio forum that they can make the time to sign on to. Subtle effects are what we have become used to dealing with when auditioning audio “tweaks”.

Well, that’s not what is happening here. The changes wrought by those $10 inner tubes are more on a par with swapping out a pair of good 20 year-old loudspeakers for a pair of modern high-performance units. The basis is deeper and fuller, with less overhang and more tuneful delineation of pitch. The stereo image is tighter, much deeper, and more holographic. A whole layer of grain that I didn’t even know was there has seemingly been stripped from the midrange. Vocals in particular seem more natural and more three-dimensional. I could go on, but I won’t because the specifics of what I am hearing may prove to be specific to my particular system. However, I don’t think that the general level of benefits are going to be all that system-specific. We are talking about mechanical isolation, and I don’t think my PS Audio components depart in any radical way from industry norms with regard to their mechanical standard of construction. I expect major noticeable improvements are going to be evident regardless of what system you are using.

You might well point out that the BHK300 monoblocks contain vacuum tubes, and that vacuum tubes are well known for being particularly microphonic, and you would be right. But on the other hand I listened for a short while with inner tubes only underneath the BHK300 monoblocks, and when I placed the third inner tube under the P10 PowerPlant – which contains no vacuum tubes – the magnitude of the change was just as large, if not larger, and was probably more impressive in terms of the qualitative improvements it brought. Whereas the inner tubes under the monoblocks brought immediate and indisputable benefits, it was not until the final tube was placed under the P10 that everything suddenly came together as a coherent whole.

This was originally conceived as a trial experiment. The idea was to see how it went, and decide where to go next. In truth I’m not sure where to go next. All I know is I am going to focus on enjoying the music until the inner tubes eventually burst or deflate or whatever it is they are going to do. I expect stability and longevity is going to limit their long-term practicality, but until it does I’m going to be enjoying it for what it is doing right now.

This new version includes significant updates to our Gen-IV audio engine. These changes result in subtle improvements to the sound quality – although some of you (me, for example!) might consider that “subtle” doesn’t quite do it justice! I guess it is going to be somewhat system-dependent. We also include a couple of bug fixes which eliminate unexpected crashes that can occur with certain types of (mostly multi-channel) DAC.

As usual, BitPerfect 3.1 is a free upgrade to all existing BitPerfect users.

Today Apple released update 12.4.1 for iTunes. I have been testing it, and not only does it work fine with BitPerfect, it also fixes whatever was causing the problem with “Minimize iTunes Interaction” mode that occurred with iTunes 12.4.0, so BitPerfect users who prefer that mode of operation can feel confident enough to try enabling it again. However, it will still be necessary to disable and re-enable BitPerfect after making the change in order for it to come into effect.

We are pretty sure we have homed in on the problem that can cause loops of ~6 seconds duration in playback with this new software update. It is associated only with iTunes 12.4, and only affects playback in “Minimize iTunes Interaction” mode. The solution is to avoid using this mode. However, it appears that additional steps are required to turn this mode off (or on). First uncheck the “Minimize iTunes Interaction” check box in the iTunes tab of BitPerfect’s Preferences Window. Next, close the Preferences Window, and select “Disable BitPerfect” from BitPerfect’s menu bar drop-down menu. Finally, re-enable BitPerfect again by selecting “Enable BitPerfect” from BitPerfect’s menu bar drop-down menu.

I have been using this combination all day yesterday with “Minimize iTunes Mode” disabled, and have encountered no further problems. I am also getting feedback from some of our users who have been trying out this fix for me, and it seems they are also reporting no further problems. Therefore I am cautiously recommending to BitPerfect users that you can safely make this update if you choose to do so, provided you follow the measures I described.

For the time being we still don’t know what the specific root cause is, but when we do find out, if a workaround can be found to re-enable “Minimize iTunes Interaction” mode we will include it in our next version update.

Apple has released another simultaneous update to both OS X and iTunes. Early testing has shown some possible compatibility problems with BitPerfect after making this upgrade. The problem causes BitPerfect to play in a continuous ~6 second loop. While we believe we have identified a potential workaround for this problem, the combined nature of the problem together with the (simple) fix means that once the fix is in place we are unable to re-create the problem. This means that testing the fix becomes a little bit challenging.

We are working with a few users to test out our solution and make sure that it does in fact work for everybody. But in the meantime, we recommend that BitPerfect users avoid this particular upgrade until I am in a position to communicate further on the subject.